mailing list archives
Re: Digital Unix 4.0E /var permission
From: implosion () BROKEN NE MEDIAONE NET (implosion)
Date: Tue, 6 Apr 1999 10:18:28 -0500
First of all, under Digital UNIX, the system group is the group that is
'pseudo-root', i.e. have near root privilages and are allowed to su into
root. /var, which under a default install, is a sym-link to /usr/var,
contains all of the system accounting files, LSM, and other system
specific files that all System Administrators would need to run thier
system. So, it is only logical that system have write permissions to that
Also, one should note that any system administrator should (and
would, I would hope), only put _secure_ accounts in the system group, i.e.
any account that is going to utilize a safe password and those accounts
are not going to have set-uid or gid executables attached to them.
One more note: as an ls -la of /sbin/rc3.d would show you,
S95xlogin is only a sym-link to /sbin/init.d/xlogin. The S95 is there so
when init comes up to run level 3, it will start (the S tells it that),
and the 95 is placed there to put it in order - you add a numeric number
to the front of the executable, so when the rc3 script processes
/sbin/rc3.d, it gets launched after certain daemons and programs that need
to be running in order for it to start. To the best of my knowledge,
xlogin isnt doing anything to the /var permissions.
On Sun, 4 Apr 1999, Harhalakis Stefanos wrote:
On Digital Unix 4.0E with the latest patch kit aplied, after a new
installation /var has g+w for group system. Anyone that can crack any
account with gid==system may exploit this (not tested but there should be
no problem with mv'ing /var/sbin, /var/adm etc etc..). It seems that CDE
is forcing g+w to /var.. The whole thing is done while executing
/sbin/rc3.d/S95xlogin and only if CDE is selected.
Digital Unix 4.0E /var permission Harhalakis Stefanos (Apr 04)